Applying a sunburst
Applying a three color sunburst is possible with just rattle cans, but it takes practice! StewMac has a great posting on how to accomplish this which I used as base. I won't repeat what they have explained, but I will provide help tips and potential pitfalls that I discovered during this process. With any luck, I will save you some time and grief.
I can't stress this enough. Find a scrap of wood and cut it in the rough shape of a guitar. It doesn't have to be the same size or look anywhere perfect. You can use this in the future for sampling colors and testing other finishing methods.
Follow the StewMac steps and see how it turns out. Experiment with the size of the paper mask. Test out different colors for the sunburst effect.
Blacken edges and amber insides are the easy part
Don't worry too much about overspray. You can always sand off the areas on top if you've accidently made some stripes.
Spraying the interior with a lighter color is very simple because it's too light to change the color of the black.
Good thing you practiced, because now it's time to blend it all together. Always keep the spray can at 45 degrees and make light passes. This is where your creativity comes in and it's up to you to decided when it's done. Take your time.
Don't clear coat just yet!
So you've created your masterpiece and you're ready to gloss it all up. Hold on! While you may not have splattered dots of brown or whatever blending color used on the very interior of the guitar, there is a very fine layer of "dust" all over. Depending on how you've handled the guitar you could wipe it off in some areas but not others. Once a clear coat goes on, it sticks out like a sore thumb! Give it a good look either wipe it all off with a tack rag.